I'm working on a 9100A, and there are two keys that refuse to move
whatsoever: enter and plus. Upon removal of the keyboard assembly and
opening it up, I believe I see spots of corrosion on those key stalks.
Any ideas on how to correct the issue?
The other night I picked up a TRS-80 model II from a seller on Craigslist. The computer had apparently belonged to an account and it came with lots of binders of TRS-80 accounting software manuals and boxes of disks filled with old client information.
It came with some no-name 3rd party external dual 8" drive and a gigantic Centronics 703(?) printer. I tested out the computer when I got home and it looks like it probably works fine, I was able to power it up without any smoke coming out and get it to boot into one of the CP/M disks I found in the box. The keyboard is another matter, but I've already been pointed to a few sites that discuss how to deal with the foam pads inside the capacitive keyboard.
I didn't get a cable for either the printer or the external disks, although I'm not really worried about hooking up to the parallel port since I doubt I'm really going to want to print from the TRS-80 anyway. I did open up the external drive case and it has two genuine Shugart drives in it, and I've already ordered some 50 pin IDC connectors so I can make up a cable to connect it to the TRS-80.
I'm having a heck of a time hunting down a manual for the printer though. I *think* it's a Centronics 703, but the 703 was blacked out on the nameplate on the back, and there's no identification on the front. I definitely need to get a new ribbon for it, but it looks like instead of replacing the ribbon as a cartridge, you pull the whole ribbon out of the screwed in case and then have to pack a new one in. The pinch rollers for feeding the ribbon are pretty old and now flat on one side, but after a touch of oil they do *seem* to be turning and feeding the ribbon.
I've posted an album up on Google+ of the computer, you can see it here:
Along with the Tandy 1000 that I brought home the other day, I also got the
monitor plinth (just not the original monitor itself). Mounted on the
underside of the plinth are rubber feet, and these appear to have "eaten"
into the top of the 1000's plastic case.
Has anyone seen this kind of interaction before? In the hundreds of vintage
systems I've seen, I've come across many cases of rubber parts
deteriorating (and sometimes turning to goo), but not of it damaging other
materials (and in this instance the rubber feet themselves seem to be in
good condition still)
I'm not sure how widespread this is, and/or if it's going to be more of a
problem as things age. On the other hand, I'm inclined to think that this
is an isolated incident, and maybe related to aggressive cleaning materials
used on the machine's case (which then softened the plastic) - there are
more imprints on the case shell than there are feet on the plinth, so it
happened at least twice with the plinth moved in the meantime.
While digging through a local estate sale yesterday, I found an unknown
(to me), unmarked system. From what I know of the late owner, the system
may be related to the aircraft industry, as many of his tools and bits and
bobs were from Boeing surplus.
As for the unit itself, it is a yellow desk, with a tinted glass
slide-down screen, a complex keyboard. It had two Canon 5.25" floppy
drives mounted behind the screen, next to a USi Pi3 amber monitor. The
bottom section of the desk had a card cage, with cards, but I was unable to
open it for inspection. The only IO I found was a 36 pin Centronics
connection on the lower back of the desk. The console itself has a red
Fault indicator, as well as 3 columns of indicator lamps, with a
corresponding button and markings 1-8. There are also light up
push-buttons for power, load, reset, and compute.
The keyboard has switches for parity select (odd/even), Logic (+/-), Caps
(vs mixed upper/lower), Aux on/off, repeat fast/slow, some sort of counter,
plus a pair of mode A/B select wheels.
Pics can be seen at http://microfilmks.com/~tesla/Oddball/
I'm curious about what sort of software might have been used during the 1980s on VAX-11/7xx series machines to support design and/or production of electronic hardware.
If there are any dusty old archived copies of such software that I might be able to experiment with on my VAX-11/730 (after I get it running, that is), that would be pretty exciting.
Mark J. Blair, NF6X <nf6x at nf6x.net>
On Mon, 23 Jun 2014 14:52:25 -0700:00, Ian McLaughlin <ian at platinum.net>
> Hello all and thank you for adding me to the list.
> I am in the process of restoring a NorthStar Horizon machine. The boards in this machine
> have a significant amount of flux residue on them - it certainly appears that this
> particular machine was constructed from a kit. My question is about this flux - should I
> be removing it as part of my cleanup, or should I leave it in place? I know that this
> isn't a super-collectible machine or anything, but I've never come across this issue in
> any other machine in my collection, and I was wondering what the general consensus was.
> I'm perfectly aware of the corrosive nature of the flux and how to remove it, however this
> flux has been there for 35+ years.
> Thanks in advance for your thoughts.
It is probably resin (or rosin) core solder, which is most likely not
corrosive. You will know by the smell if you put a hot iron to a solder
joint. Resin is a medium brown which darkens when heated. If you want to
remove it, resin dissolves in ethanol. If it has been there for 35 years
with no ill effects, you may as well leave it.
Hello all and thank you for adding me to the list.
I am in the process of restoring a NorthStar Horizon machine. The boards in this machine have a significant amount of flux residue on them - it certainly appears that this particular machine was constructed from a kit. My question is about this flux - should I be removing it as part of my cleanup, or should I leave it in place? I know that this isn't a super-collectible machine or anything, but I've never come across this issue in any other machine in my collection, and I was wondering what the general consensus was. I'm perfectly aware of the corrosive nature of the flux and how to remove it, however this flux has been there for 35+ years.
Thanks in advance for your thoughts.
My saved searches coughed up a TU55 single-drive DECtape transport on the eBay this morning. Then I looked at the listing and had a stunning case of sticker shock, as it's listed for $6,900 buy it now. !
I know (?) that TU55/TU56 drives aren't too common these days, but is that price in line with what they go for?
P.S.: No, I'm not even considering buying it. I'm just morbidly curious.
Mark J. Blair, NF6X <nf6x at nf6x.net>
[TRS-80 M2 and printer]
>> I didn't get a cable for either the printer or the external disks,
> I'm having a heck of a time hunting down a manual for the printer
> though. I *think* it's a Centronics 703, but the 703 was blacked out
> on the nameplate on the back, and there's no identification on the
> front. I
Whenever I read a thread that starts with something like "...picked up a TRS
80 Model II..." my first instinct is RUN! Before it's too late! I am very
happy with a single drive system for most things BTW. But I also have a
troublesome external drive to use when I need more aggravation in my life,
or a feeling shame and doubt about my abilities to support vintage hardware.
But seriously, I have posted a bunch of new TRS 80 Model II images on my
site, that have been vetted by the TRS Yahoo group. You might find useful.